Crested penguins breeding chiefly at the remote subtropical
“maritime” Tristan da Cunha and Gough Islands (ca. 85% of the population), along with small numbers at Amsterdam
and St. Paul Islands (taxon moseleyi)
have, until fairly recently, been treated as a subspecies of the well-studied
subantarctic Rockhopper Penguin E.
chrysocome. A growing number of recently published papers have induced most
authorities to accept moseleyi as a
separate species. Subspecies filholi
of subantarctic Heard Island and Macquarie Island has not been recorded in the
SACC region, and its taxonomic position is controversial. This proposal is
necessary due to the post-1995 appearance of documented vagrant Eudyptes [chrysocome] moseleyi
penguins at the Falkland Islands.

A NO vote for part a) disqualifies a vote for part b). If
added to the SACC list, a decision on an English vernacular name will also be
required, because at least five different names are available.

(A).Split Eudyptes moseleyi from E. chrysocome.

Evidence

Jouventin (1982) provided sonograms of moseleyi and chrysocome
showing that the former has considerably lower-pitched frequency calls, and
first drew attention to differences in behaviour, noting also the better known
distinctions in morphology (moseleyi
is larger) and plumage (moseleyi has
exceedingly long laterally splayed head plumes, unlike the short, narrow plumes
in chrysocome and several other Eudyptes penguins); visually these
penguins look very different. He suggested that moseleyi could be elevated to species rank.

A more thorough study (Jouventin et al. 2006) included DNA sequences of the ND2 gene and
mitochondrial control region, breeding cycle, further studies of voice and of
head ornamentation; the conclusion reached was that moseleyi warrants species rank, and also considering that “divergence in mating signals …. may have been enough to
isolate these taxa without the need for morphological differentiation.”
Jouventin et al. (2006) synthesized
the vocal and morphological evidence as follows: “The northern populations have
a much lower-pitched nuptial call (2-3 kHz for the maximum frequency vs. 6-7
kHz in the southern populations) with a completely different structure (longer
modulated phrases and fewer syllables), and longer (79-81 mm vs. 66-68 mm) and
denser yellow crest feathers than the southern form.” Biogeographically, the
main breeding areas of moseleyi
(subtropical) and chrysocome
(subantarctic) are separated by the Subtropical Convergence, which divides
subantarctic and subtropical waters (see the especially synthetic Fig. 1 in
Jouventin et al. 2006).

Thereafter, Banks et
al. (2006) analysed 1441 nucleotides of three mitochondrial genes to 1)
reconstruct the phylogenetic relationships, and 2) to compare the genetic
distances between the Rockhopper taxa and compared this with the uncorrected
pairwise distances between other sister penguin species. Phylogenetically, all
three taxa (moseleyi, chrysocome, filholi) were monophyletic with the latter two representing a
sister position to one another. With regard to the genetic distances, in the
first gene (ribosomal), chrysocome–moseleyi was more divergent than Spheniscus mendiculus–S. humboldti (two
species on the SACC list), and S.
magellanicus–S. demursus, both of
which showed a similar divergence as chrysocome
– filholi. The cytochrome b
analysis showed a similar genetic distance between chrysocome–moseleyi compared
to filholi–moseleyi but slightly less than E.
pachyrhynchus–robustus and mendiculus–humboldti.
In the final gene test (cytochrome oxidase), chrysocome–moseleyi came
out as being more divergent than
mendiculus–humboldti, than E.
chrysolophus–schlegeli and chrysocome-filholi, each of which showed a
similar divergence. In synthesis, genetic (mtDNA) data supports the split of moseleyi from chrysocome, but the position of filholi
is more open to alternative interpretation.

Demogin et al.
(2010) studied the reversed hatching asynchrony comparing the egg size dimorphism
in the three Rockhopper taxa, finding that chrysocome
has considerably larger volume eggs and higher breeding success than either moseleyi or filholi.

In addition to the above, there are also published data on
host-exclusive and non-exclusive lice in the different Rockhopper taxa if
anyone needs more evidence.

Most recent authorities have accepted the moseleyi split and sometimes also the filholi split, based principally on the
work of Banks et al. 2006. The one
exception is Christidis and Boles (2008), who stated “Genetic distances between
the northern [moseleyi] and southern
[chrysocome] forms were about half
that between E. chrysocome (sensu lato) and E. chrysolophus.’’ Note that I was unable to find this data in
Banks et al. 2006, or in any other
paper; indeed this statement actually contradicts the study of Banks et al. 2006. They went on to state… “The
observed level of difference between northern and southern forms of E. chrysocome is comparable to those
between the pairs E. chrysolophus-–schlegeli
and E. pachyrhynchus–robustus
(Ritchie 2001), which are here treated as conspecific.”Oddly, the Ritchie (2001) paper deals
with DNA markers relating to Pygoscelis
adeliae. I am at a loss to explain or qualify any of the comments made by
Christidis and Boles (2008), which appear to be erroneous.

Recommendation

I would suggest that the collective evidence strongly
favours a YES vote that would recognise Eudyptes
moseleyi as a valid species. A NO vote would imply that SACC has to review
the validity of various penguin species on its main list and Hypothetical list,
with a view to lumping, in particular Spheniscus
mendiculus into S. humboldti, S. magellanicus into S. demursus, E. robustus into E.
pachyrhynchus (there is a reasonable case for this anyway), and E. schlegeli into E. chrysolophus.

(B).Add Eudyptes
moseleyi to the main SACC list.

Evidence

Matias et al.
(2009) documented the first four records of Eudyptes
moseleyi at the Falkland Islands, coming from East Falkland from late
November to late December 1995, and again in late November 1996, at Kidney
Island in mid December 2004, and at New Island in late November 2004 with two
published photographs from New Island and McBride Head, East Falkland. The
diagnostic, long splayed and drooping head plumes and blunt-tipped supercilium
in both photographs leave no doubt regarding the identification while the
ventral flipper pattern, visible in one photograph, provides yet more
diagnostic features. Subsequently, another bird was photographed on the
Falklands in December 2009, and another in December 2010-January 2011;
photographs available on Internet.

Recommendation: I recommend a YES vote to add E. moseleyi to the SACC list as a
confirmed vagrant (V) to the Falkland Islands. A NO vote would refute the
identification of the published records.

Ritchie,
P.A. 2001. The evolution of the mitochondrial DNA control region in the Adelie
Penguins of Antarctica. Massey Univ., Palmerston North, New Zealand.

Mark
Pearman, October 2011

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Comments from Robbins:“YES, to
elevating moseleyi to species
level.All data suggest that this
is a split long overdue.Also, yes
to adding this to the SACC list.”

Comments from Stiles:“YES.There seems to be good evidence from a
variety of sources for this split, along with adding moseleyi to the SACC list.”

Comments
from Pérez:
“YES. Complete evidence supports this
split, including morphological, genetic, and behavioral information. Christidis
and Boles (2008) were against the split, based on genetic distances, but this seems
to be a mistake because Jouventin et al. (2006) showed the complete opposite
pattern. Also YES to adding this species to the SACC list. Observations of both
taxa (E. chrysocome and E. moseleyi) in Falkland Islands,
assuming lack of morphological overlap (as suggested by evidence given by Mark
in the proposal), support species status. However, it would be interesting to
do a population genetic study in Falkland Islands to confirm there is no genetic
introgression between these taxa, as I don’t think published evidence discard
this possibility (no more than five E. chrysocome individuals (no moseleyi
for Falkland Islands) sequenced; Banks et al (2006)).”